better separation of execution logic from CLI

[msusta]

At the moment the CLI handler is hosting most of the actual execution logic while being tied to the CLI input. It'd be nice if the logic got moved somewhere separately to better accept arguments from other inputs without the need to rewrite most of the cli.py code.

[pas256]

Totally agree. I kind of designed it with core.Distami being kind of the API, and CLI being the process, but really the CLI and process should be separated as well.

[msusta]

Guess the exec logic here is the copy() function and parallel copy setup. So no matter the input / parser the data should be:

• AMI ID
• AMI Region
• Regions to copy to
• Accounts to share with

So the CLI should be left only with arg parser and the functionality moved somewhere in core. It can be probably in it's own class to still allow using Distami without change.

[pas256]

Right. I would like it to be its own class as core is already doing enough